# 两个 3 行 3 列的矩阵，实现其对应位置的数据相加，并返回一个新矩阵：

X = [[12, 7, 3],
     [4, 5, 6],
     [7, 8, 9]]

Y = [[5, 8, 1],
     [6, 7, 3],
     [4, 5, 9]]

result = [[0, 0, 0],
          [0, 0, 0],
          [0, 0, 0]]

# 迭代输出行
for i in range(len(X)):
    # 迭代输出列
    for j in range(len(X[0])):
        result[i][j] = X[i][j] + Y[i][j]

for r in result:
    print(r)